Derivative Instruments (Outstanding Derivative Instruments With Off-Balance-Sheet Risks) (Details) - USD ($) $ in Millions		Dec. 31, 2018	Dec. 31, 2017
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts		$ 137,497	$ 110,350
Asset Fair Value		2,529	2,563
Liability Fair Value		1,793	2,563
Interest rate contracts [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	[1]	104,637
Foreign currency contracts [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	[2]	2,373
Equity market contracts [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts		30,487
GLB Ceded Embedded Derivatives [Member] | Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member]
Outstanding derivative instruments with off-balance-sheet risks
Asset Fair Value	[3],[4]	72	51
Liability Fair Value	[3],[4]		67
Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts		5,067	4,811
Asset Fair Value		237	125
Liability Fair Value		48	163
Derivative investments [Member] | Interest rate contracts [Member] | Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	[5]	100,628	72,937
Asset Fair Value	[5]	464	657
Liability Fair Value	[5]	138	127
Derivative investments [Member] | Foreign currency contracts [Member] | Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	[5]	47	22
Derivative investments [Member] | Equity market contracts [Member] | Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	[5]	30,487	31,090
Asset Fair Value	[5]	676	562
Liability Fair Value	[5]	162	557
Derivative investments [Member] | Credit contracts [Member] | Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	[5]		52
Derivative investments [Member] | Cash Flow Hedges [Member] | Interest rate contracts [Member] | Designated as Hedging Instrument [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	[5]	2,741	3,007
Asset Fair Value	[5]	70	46
Liability Fair Value	[5]	9	84
Derivative investments [Member] | Cash Flow Hedges [Member] | Foreign currency contracts [Member] | Designated as Hedging Instrument [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	[5]	2,326	1,804
Asset Fair Value	[5]	167	79
Liability Fair Value	[5]	39	79
Derivative investments [Member] | Fair Value Hedges [Member] | Interest rate contracts [Member] | Designated as Hedging Instrument [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	[5]	1,268	1,438
Asset Fair Value	[5]	55	254
Liability Fair Value	[5]	137	174
Other Assets [Member] | GLB Direct Embedded Derivatives [Member] | Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member]
Outstanding derivative instruments with off-balance-sheet risks
Asset Fair Value	[3]	123	903
Reinsurance Related Embedded Derivatives [Member] | Embedded derivatives-Reinsurance related [Member] | Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member]
Outstanding derivative instruments with off-balance-sheet risks
Liability Fair Value	[6]	3	57
Future Contract Benefits [Member] | Indexed Annuity And Embedded Derivatives [Member] | Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member]
Outstanding derivative instruments with off-balance-sheet risks
Asset Fair Value	[3],[7]	902	11
Liability Fair Value	[3],[7]	$ 1,305	$ 1,418

[1] As of December 31, 2018, the latest maturity date for which we were hedging our exposure to the variability in future cash flows for these instruments was April 2067.

[2] As of December 31, 2018, the latest maturity date for which we were hedging our exposure to the variability in future cash flows for these instruments was September 2049.

[3] Reported in other assets on our Consolidated Balance Sheets.

[4] Reported in other liabilities on our Consolidated Balance Sheets.

[5] Reported in derivative investments and other liabilities on our Consolidated Balance Sheets.

[6] Reported in reinsurance related embedded derivatives on our Consolidated Balance Sheets.

[7] Reported in future contract benefits on our Consolidated Balance Sheets.